My MacBook Pro has been hacked

I never use my MacBook only like once a month because I have no choice to maintain my online business and I went to use it and there was a third user on it then it changed my user name to guest and then my touchpad started to freak out I had no control over my settings system preferences is gone it wouldn’t except my Apple ID or password and it had a pop up that said it couldn’t verify my account and I have all my information on my iPhone working my Apple ID and password still works but slowly it’s changing things on my iPhone I have apps on it safari I never use has I history of places I never been to my spectrum account trying to access it I use the app to do everything on it my old Etsy shop was on it I had search history when I wasn’t using my iPhone because it’s showing the day and time which I couldn’t have been on it my drive has all my business the entire folders products pictures of items now it shows in my files all my information and everything that’s basically my entire life and everything that’s I can’t ever get back so I had to take down my website and close my Etsy shop there is no way my MacBook could have gotten all of these things and there more then what I’m telling you I have no personal information or download any apps emails my WiFi is fine my Bluetooth is gone there no adapter my settings are gone I seriously don’t use it I only use chrome Squarespace Etsy and a photo editing app I can’t fix anything because my touchpad doesn’t work it’s out of control all the place opening apps files I can’t stop it and try to keep it on a tap to try and do my school work I had to drop out I never use it so I don’t know how this happened my iPhone is attached to it so how do I fix if the MacBook it’s only 6 months old it’s ruined my business my college degree I have one semester left until I graduate I have a workspace email account never have I done anything that might have caused it. I was told to wipe it clean but it won’t accept my login information even when I’ve changed it I try after that and it doesn’t work my accounts on my iPhone are at risk